Largely as a consequence of the aging of the population, rates of physical disability have risen significantly over the decade of the 90's and substantial additional increases are projected. As of 1992 more than 10 percent of Americans 18 to 64 years of age and more than 23 percent of those 65 and older were experiencing significant activity limitations. Despite the current and anticipated burden of physical disability in the population, very little is known about the significance of such disability with respect to substance abuse or mental health problems. The most general goals of the proposed study are to assess lifetime and current substance use, abuse and dependence, and the lifetime and recent occurrence of psychiatric disorders, as they vary with the presence and severity of physical disability, and to identify potentially modifiable risk and protective factors associated with these outcomes, within and across the presence and/or severity of disability. Only such information can provide a rational basis for estimating the nature and degree of intervention need associated with physical disability and for identifying promising intervention targets. It is also crucial to understand ethnic/racial differences in substance/mental health risk associated with disability and in factors associated with degree of risk. With emphasis on the unique and understudied Hispanic population found in South Florida, this also represents one of the general goals of the proposed study. A two-wave panel study is proposed of representative community residing samples of Cuban (25 percent), other Hispanic (25 percent), African American (25 percent), and non-Hispanic white (25 percent) persons, 18 years of age and older, with activity limitations deriving from physical causes (n = 1200), and of their age, sex, ethnicity/race, and area of residence counterparts without physical disabilities (n = 1200).